Diseases Commons^™

Super-Resolution Microscopy Reveals Photoreceptor-Specific Subciliary Location And Function Of Ciliopathy-Associated Protein Cep290, Valencia L Potter, Abigail R Moye, Michael A Robichaux, Theodore G Wensel

Faculty, Staff and Students Publications

Mutations in the cilium-associated protein CEP290 cause retinal degeneration as part of multiorgan ciliopathies or as retina-specific diseases. The precise location and the functional roles of CEP290 within cilia and, specifically, the connecting cilia (CC) of photoreceptors, remain unclear. We used super-resolution fluorescence microscopy and electron microscopy to localize CEP290 in the CC and in the primary cilia of cultured cells with subdiffraction resolution and to determine effects of CEP290 deficiency in 3 mutant models. Radially, CEP290 localizes in close proximity to the microtubule doublets in the region between the doublets and the ciliary membrane. Longitudinally, it is distributed throughout …

Phds/Cpt1b/Vdac1 Axis Regulates Long-Chain Fatty Acid Oxidation In Cardiomyocytes, Aude Angelini, Pradip K Saha, Antrix Jain, Sung Yun Jung, Randall L Mynatt, Xinchun Pi, Liang Xie

Faculty, Staff and Students Publications

Cardiac metabolism is a high-oxygen-consuming process, showing a preference for long-chain fatty acid (LCFA) as the fuel source under physiological conditions. However, a metabolic switch (favoring glucose instead of LCFA) is commonly reported in ischemic or late-stage failing hearts. The mechanism regulating this metabolic switch remains poorly understood. Here, we report that loss of PHD2/3, the cellular oxygen sensors, blocks LCFA mitochondria uptake and β-oxidation in cardiomyocytes. In high-fat-fed mice, PHD2/3 deficiency improves glucose metabolism but exacerbates the cardiac defects. Mechanistically, we find that PHD2/3 bind to CPT1B, a key enzyme of mitochondrial LCFA uptake, promoting CPT1B-P295 hydroxylation. Further, we …

Cellular Regeneration As A Potential Strategy To Treat Cardiac Conduction Disorders, Satadru K Lahiri, Mohit M Hulsurkar, Xander Ht Wehrens

Faculty, Staff and Students Publications

Loss of atrioventricular conduction system (AVCS) cells due to either inherited or acquired deficits leads to conduction diseases, which can deteriorate into fatal cardiac arrhythmias and sudden death. In this issue of the JCI, Wang et al. constructed a mouse model of atrioventricular block (AVB) by inducing AVCS cell-specific injury using the Cx30.2 enhancer to drive expression of diphtheria toxin fragment A. AVCS cell ablation in adult mice led to irreversible AVB. jkjkIn contrast, AVCS cell injury in neonatal mice was followed by spontaneous recovery in a subset of mice, revealing a limited postnatal time window during which the regeneration …

The Efficacy Of Insecticide-Treated Window Screens And Eaves Against Anopheles Mosquitoes: A Scoping Review, Beverly Anaele, Karan Varshney, Francis S O Ugwu, Rosemary Frasso

College of Population Health Faculty Papers

Background: Female mosquitoes serve as vectors for a host of illnesses, including malaria, spread by the Plasmodium parasite. Despite monumental strides to reduce this disease burden through tools such as bed nets, the rate of these gains is slowing. Ongoing disruptions related to the COVID-19 pandemic may also negatively impact gains. The following scoping review was conducted to examine novel means of reversing this trend by exploring the efficacy of insecticide-treated window screens or eaves to reduce Anopheles mosquito bites, mosquito house entry, and density.

Methods: Two reviewers independently searched PubMed, Scopus, and ProQuest databases on 10 July, 2020 for …

Ucp3 (Uncoupling Protein 3) Insufficiency Exacerbates Left Ventricular Diastolic Dysfunction During Angiotensin Ii-Induced Hypertension, Xu Chen, Sadia Ashraf, Nadia Ashraf, Romain Harmancey

Faculty, Staff and Student Publications

Background Left ventricular diastolic dysfunction, an early stage in the pathogenesis of heart failure with preserved ejection fraction, is exacerbated by joint exposure to hypertension and obesity; however, the molecular mechanisms involved remain uncertain. The mitochondrial UCP3 (uncoupling protein 3) is downregulated in the heart with obesity. Here, we used a rat model of UCP3 haploinsufficiency (ucp3

Ankyrin-Dependent Na+ Channel Clustering Prevents Neuromuscular Synapse Fatigue, Chuansheng Zhang, Abhijeet Joshi, Yanhong Liu, Ozlem Sert, Seth G Haddix, Lindsay H Teliska, Anne Rasband, George G Rodney, Matthew N Rasband

Faculty, Staff and Students Publications

Skeletal muscle contraction depends on activation of clustered acetylcholine receptors (AchRs) and muscle-specific Na+ channels (Nav1.4). Some Nav1.4 channels are highly enriched at the neuromuscular junction (NMJ) and their clustering is thought to be essential for effective muscle excitation. However, this has not been experimentally tested, and how NMJ Na+ channels are clustered is unknown. Here, using muscle-specific AnkyrinR, AnkyrinB, and AnkyrinG single, double, and triple-conditional knockout mice we show that Nav1.4 channels fail to cluster only after deletion of all three ankyrins. Remarkably, ankyrin-deficient muscles have normal NMJ morphology, AchR clustering, sarcolemmal levels of Nav1.4, and muscle force, and …

Endothelium-Specific Depletion Of Lrp1 Improves Glucose Homeostasis Through Inducing Osteocalcin, Hua Mao, Luge Li, Qiying Fan, Aude Angelini, Pradip K Saha, Cristian Coarfa, Kimal Rajapakshe, Dimuthu Perera, Jizhong Cheng, Huaizhu Wu, Christie M Ballantyne, Zheng Sun, Liang Xie, Xinchun Pi

Faculty, Staff and Students Publications

The vascular endothelium is present within metabolic organs and actively regulates energy metabolism. Here we show osteocalcin, recognized as a bone-secreted metabolic hormone, is expressed in mouse primary endothelial cells isolated from heart, lung and liver. In human osteocalcin promoter-driven green fluorescent protein transgenic mice, green fluorescent protein signals are enriched in endothelial cells lining aorta, small vessels and capillaries and abundant in aorta, skeletal muscle and eye of adult mice. The depletion of lipoprotein receptor-related protein 1 induces osteocalcin through a Forkhead box O -dependent pathway in endothelial cells. Whereas depletion of osteocalcin abolishes the glucose-lowering effect of low-density …

Structure And Dynamics Of Photoreceptor Sensory Cilia, Theodore G Wensel, Valencia L Potter, Abigail Moye, Zhixian Zhang, Michael A Robichaux

Faculty, Staff and Students Publications

The rod and cone photoreceptor cells of the vertebrate retina have highly specialized structures that enable them to carry out their function of light detection over a broad range of illumination intensities with optimized spatial and temporal resolution. Most prominent are their unusually large sensory cilia, consisting of outer segments packed with photosensitive disc membranes, a connecting cilium with many features reminiscent of the primary cilium transition zone, and a pair of centrioles forming a basal body which serves as the platform upon which the ciliary axoneme is assembled. These structures form a highway through which an enormous flux of …

Primary Osteoarthritis Early Joint Degeneration Induced By Endoplasmic Reticulum Stress Is Mitigated By Resveratrol, Jacqueline T Hecht, Alka C Veerisetty, Juliana Wu, Francoise Coustry, Mohammad G Hossain, Frankie Chiu, Francis H Gannon, Karen L Posey

Faculty, Staff and Student Publications

Increasing numbers of people are living with osteoarthritis (OA) due to aging and obesity, creating an urgent need for effective treatment and preventions. Two top risk factors for OA, age and obesity, are associated with endoplasmic reticulum (ER) stress. The I-ERS mouse, an ER stress-driven model of primary OA, was developed to study the role of ER stress in primary OA susceptibility. The I-ERS mouse has the unique ability to induce ER stress in healthy adult articular chondrocytes and cartilage, driving joint degeneration that mimics early primary OA. In this study, ER stress-induced damage occurred gradually and stimulated joint degeneration …

Cd11c Participates In Triggering Acute Graft-Versus-Host Disease During Bone Marrow Transplantation, Qianqian Wang, Xiuhua Su, Yi He, Mei Wang, Donglin Yang, Rongli Zhang, Jialin Wei, Qiaoling Ma, Weihua Zhai, Aiming Pang, Yong Huang, Sizhou Feng, Christie M Ballantyne, Huaizhu Wu, Xiaolei Pei, Xiaoming Feng, Mingzhe Han, Erlie Jiang

Faculty, Staff and Students Publications

CD11c is a canonical dendritic cell (DC) marker with poorly defined functions in the immune system. Here, we found that blocking CD11c on human peripheral blood mononuclear cell‐derived DCs (MoDCs) inhibited the proliferation of CD4+ T cells and the differentiation into IFN‐γ‐producing T helper 1 (Th1) cells, which were critical in acute graft‐versus‐host disease (aGVHD) pathogenesis. Using allogeneic bone marrow transplantation (allo‐BMT) murine models, we consistently found that CD11c‐deficient recipient mice had alleviated aGVHD symptoms for the decreased IFN‐γ‐expressing CD4+ Th1 cells and CD8+ T cells. Transcriptional analysis showed that CD11c participated in several immune regulation functions including maintaining antigen …

Adipose Tissue Hyaluronan Production Improves Systemic Glucose Homeostasis And Primes Adipocytes For Cl 316,243-Stimulated Lipolysis, Yi Zhu, Na Li, Mingyang Huang, Mason Bartels, Sophie Dogné, Shangang Zhao, Xi Chen, Clair Crewe, Leon Straub, Lavanya Vishvanath, Zhuzhen Zhang, Mengle Shao, Yongjie Yang, Christy M Gliniak, Ruth Gordillo, Gordon I Smith, William L Holland, Rana K Gupta, Bingning Dong, Nathalie Caron, Yong Xu, Yucel Akgul, Samuel Klein, Philipp E Scherer

Faculty, Staff and Students Publications

Plasma hyaluronan (HA) increases systemically in type 2 diabetes (T2D) and the HA synthesis inhibitor, 4-Methylumbelliferone, has been proposed to treat the disease. However, HA is also implicated in normal physiology. Therefore, we generated a Hyaluronan Synthase 2 transgenic mouse line, driven by a tet-response element promoter to understand the role of HA in systemic metabolism. To our surprise, adipocyte-specific overproduction of HA leads to smaller adipocytes and protects mice from high-fat-high-sucrose-diet-induced obesity and glucose intolerance. Adipocytes also have more free glycerol that can be released upon beta3 adrenergic stimulation. Improvements in glucose tolerance were not linked to increased plasma …

Polyploid Giant Cancer Cells And Ovarian Cancer: New Insights Into Mitotic Regulators And Polyploidy†, Joanne S Richards, Nicholes R Candelaria, Rainer B Lanz

Faculty, Staff and Students Publications

Current first-line treatment of patients with high-grade serous ovarian cancer (HGSOC) involves the use of cytotoxic drugs that frequently lead to recurrent tumors exhibiting increased resistance to the drugs and poor patient survival. Strong evidence is accumulating to show that HGSOC tumors and cell lines contain a subset of cells called polyploidy giant cancer cells (PGCCs) that act as stem-like, self-renewing cells. These PGCCs appear to play a key role in tumor progression by generating drug-resistant progeny produced, in part, as a consequence of utilizing a modified form of mitosis known as endoreplication. Thus, developing drugs to target PGCCs and …

Neurovascular Regulation In Diabetic Retinopathy And Emerging Therapies, Liyang Ji, Hong Tian, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Diabetic retinopathy (DR) is the leading cause of vision loss in working adults in developed countries. The disease traditionally classified as a microvascular complication of diabetes is now widely recognized as a neurovascular disorder resulting from disruption of the retinal neurovascular unit (NVU). The NVU comprising retinal neurons, glia and vascular cells coordinately regulates blood flow, vascular density and permeability to maintain homeostasis. Disturbance of the NVU during DR can lead to vision-threatening clinical manifestations. A limited number of signaling pathways have been identified for intercellular communication within the NVU, including vascular endothelial growth factor (VEGF), the master switch for …

The Antimalarial Mmv688533 Provides Potential For Single-Dose Cures With A High Barrier To, James M. Murithi, Cécile Pascal, Jade Bath, Xavier Boulenc, Nina F. Gnädig, Charisse Flerida A. Pasaje, Kelly Rubiano, Tomas Yeo, Sachel Mok, Sylvie Klieber, Paul Desert, María Belén Jiménez-Díaz, Jutta Marfurt, Mélanie Rouillier, Mohammed H. Cherkaoui-Rbati, Nathalie Gobeau, Sergio Wittlin, Anne-Catrin Uhlemann, Ric N. Price, Grennady Wirjanata, Rintis Noviyanti, Patrick K. Tumwebaze, Roland A. Cooper, Philip J. Rosenthal, Laura M. Sanz, Francisco-Javier Gamo, Jayan Joseph, Shivendra Singh, Sridevi Bashyam, Jean Michel Augereau, Elie Giraud, Tanguy Bozec, Thierry Vermat, Gilles Tuffal, Jean-Michel Guillon, Jérôme Menegotto, Laurent Sallé, Guillaume Louit, Marie-José Cabanis, Marie Françoise Nicolas, Michel Doubovetzky, Rita Merino, Nadir Bessila, Iñigo Angulo-Barturen, Delphine Baud, Lidiya Bebrevska, Fanny Escudié, Jacquin C. Niles, Benjamin Blasco, Simon Campbell, Gilles Courtemanche, Laurent Fraisse, Alain Pellet, David A. Fidock, Didier Leroy

Natural Sciences and Mathematics | Faculty Scholarship

The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in …

The Antimalarial Mmv688533 Provides Potential For Single-Dose Cures With A High Barrier To, James M. Murithi, Cécile Pascal, Jade Bath, Xavier Boulenc, Nina F. Gnädig, Charisse Flerida A. Pasaje, Kelly Rubiano, Tomas Yeo, Sachel Mok, Sylvie Klieber, Paul Desert, María Belén Jiménez-Díaz, Jutta Marfurt, Mélanie Rouillier, Mohammed H. Cherkaoui-Rbati, Nathalie Gobeau, Sergio Wittlin, Anne-Catrin Uhlemann, Ric N. Price, Grennady Wirjanata, Rintis Noviyanti, Patrick Tumwebaze, Roland A. Cooper, Philip J. Rosenthal, Laura M. Sanz, Francisco-Javier Gamo, Jayan Joseph, Shivendra Singh, Sridevi Bashyam, Jean Michel Augereau, Elie Giraud, Tanguy Bozec, Thierry Vermat, Gilles Tuffal, Jean-Michel Guillon, Jérôme Menegotto, Laurent Sallé, Guillaume Louit, Marie-José Cabanis, Marie Françoise Nicolas, Michel Doubovetzky, Rita Merino, Nadir Bessila, Iñigo Angulo-Barturen, Delphine Baud, Lidiya Bebrevska, Fanny Escudié, Jacquin C. Niles, Benjamin Blasco, Simon Campbell, Gilles Courtemanche, Laurent Fraisse, Alain Pellet, David A. Fidock, Didier Leroy

Natural Sciences and Mathematics | Faculty Scholarship

The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in …

Platelet And Erythrocyte Extravasation Across Inflamed Corneal Venules Depend On Cd18, Neutrophils, And Mast Cell Degranulation, Angie De La Cruz, Aubrey Hargrave, Sri Magadi, Justin A Courson, Paul T Landry, Wanyu Zhang, Fong W Lam, Monica A Bray, C Wayne Smith, Alan R Burns, Rolando E Rumbaut

Faculty, Staff and Student Publications

Platelet extravasation during inflammation is under-appreciated. In wild-type (WT) mice, a central corneal epithelial abrasion initiates neutrophil (PMN) and platelet extravasation from peripheral limbal venules. The same injury in mice expressing low levels of the β2-integrin, CD18 (CD18hypo mice) shows reduced platelet extravasation with PMN extravasation apparently unaffected. To better define the role of CD18 on platelet extravasation, we focused on two relevant cell types expressing CD18: PMNs and mast cells. Following corneal abrasion in WT mice, we observed not only extravasated PMNs and platelets but also extravasated erythrocytes (RBCs). Ultrastructural observations of engorged limbal venules showed platelets and RBCs …

Cd8+ T Cells Inhibit Metastasis And Cxcl4 Regulates Its Function, Robiya Joseph, Rama Soundararajan, Suhas Vasaikar, Fei Yang, Kendra L Allton, Lin Tian, Petra Den Hollander, Sevinj Isgandarova, Monika Haemmerle, Barbara Mino, Tieling Zhou, Crystal Shin, Melisa Martinez-Paniagua, Aysegul A Sahin, Jaime Rodriguez-Canales, Juri Gelovani, Jeffrey T Chang, Ghanashyam Acharya, Anil K Sood, Ignacio I Wistuba, Don L Gibbons, Luisa M Solis, Michelle C Barton, Navin Varadarajan, Jeffrey M Rosen, Xiang H Zhang, Sendurai A Mani

Faculty, Staff and Students Publications

Background

The mechanism by which immune cells regulate metastasis is unclear. Understanding the role of immune cells in metastasis will guide the development of treatments improving patient survival.

Methods

We used syngeneic orthotopic mouse tumour models (wild-type, NOD/scid and Nude), employed knockout (CD8 and CD4) models and administered CXCL4. Tumours and lungs were analysed for cancer cells by bioluminescence, and circulating tumour cells were isolated from blood. Immunohistochemistry on the mouse tumours was performed to confirm cell type, and on a tissue microarray with 180 TNBCs for human relevance. TCGA data from over 10,000 patients were analysed as …

Nlrp3 Inflammasome Is A Key Driver Of Obesity-Induced Atrial Arrhythmias, Larry Scott, Anke C Fender, Arnela Saljic, Luge Li, Xiaohui Chen, Xiaolei Wang, Dominik Linz, Jilu Lang, Mathias Hohl, Darragh Twomey, Thuy T Pham, Rodrigo Diaz-Lankenau, Mihail G Chelu, Markus Kamler, Mark L Entman, George E Taffet, Prashanthan Sanders, Dobromir Dobrev, Na Li

Faculty, Staff and Students Publications

AIMS: Obesity, an established risk factor of atrial fibrillation (AF), is frequently associated with enhanced inflammatory response. However, whether inflammatory signaling is causally linked to AF pathogenesis in obesity remains elusive. We recently demonstrated that the constitutive activation of the 'NACHT, LRR, and PYD Domains-containing Protein 3' (NLRP3) inflammasome promotes AF susceptibility. In this study, we hypothesized that the NLRP3 inflammasome is a key driver of obesity-induced AF.

METHODS AND RESULTS: Western blotting was performed to determine the level of NLRP3 inflammasome activation in atrial tissues of obese patients, sheep, and diet-induced obese (DIO) mice. The increased body weight in …

Rap1 In The Vmh Regulates Glucose Homeostasis, Kentaro Kaneko, Hsiao-Yun Lin, Yukiko Fu, Pradip K Saha, Ana B De La Puente-Gomez, Yong Xu, Kousaku Ohinata, Peter Chen, Alexei Morozov, Makoto Fukuda

Faculty, Staff and Students Publications

The hypothalamus is a critical regulator of glucose metabolism and is capable of correcting diabetes conditions independently of an effect on energy balance. The small GTPase Rap1 in the forebrain is implicated in high-fat diet-induced (HFD-induced) obesity and glucose imbalance. Here, we report that increasing Rap1 activity selectively in the medial hypothalamus elevated blood glucose without increasing the body weight of HFD-fed mice. In contrast, decreasing hypothalamic Rap1 activity protected mice from diet-induced hyperglycemia but did not prevent weight gain. The remarkable glycemic effect of Rap1 was reproduced when Rap1 was specifically deleted in steroidogenic factor-1-positive (SF-1-positive) neurons in the …

Ube2i Deletion In Adipocytes Causes Lipoatrophy In Mice, Aaron R Cox, Natasha Chernis, Kang Ho Kim, Peter M Masschelin, Pradip K Saha, Shawn M Briley, Robert Sharp, Xin Li, Jessica B Felix, Zheng Sun, David D Moore, Stephanie A Pangas, Sean M Hartig

Faculty, Staff and Students Publications

OBJECTIVE: White adipose tissue (WAT) expansion regulates energy balance and overall metabolic homeostasis. The absence or loss of WAT occurring through lipodystrophy and lipoatrophy contributes to the development of hepatic steatosis and insulin resistance. We previously demonstrated that sole small ubiquitin-like modifier (SUMO) E2-conjugating enzyme Ube2i represses human adipocyte differentiation. The role of Ube2i during WAT development remains unknown.

METHODS: To determine how Ube2i impacts body composition and energy balance, we generated adipocyte-specific Ube2i knockout mice (Ube2i

RESULTS: Surprisingly, Ube2i

CONCLUSIONS: Our results demonstrate that Ube2i expression in mature adipocytes allows WAT expansion during postnatal growth. Deletion of Ube2i in …

A Neural Basis For Brain Leptin Action On Reducing Type 1 Diabetic Hyperglycemia, Shengjie Fan, Yuanzhong Xu, Yungang Lu, Zhiying Jiang, Hongli Li, Jessie C Morrill, Jing Cai, Qi Wu, Yong Xu, Mingshan Xue, Benjamin R Arenkiel, Cheng Huang, Qingchun Tong

Children’s Nutrition Research Center Staff Publications

Central leptin action rescues type 1 diabetic (T1D) hyperglycemia; however, the underlying mechanism and the identity of mediating neurons remain elusive. Here, we show that leptin receptor (LepR)-expressing neurons in arcuate (LepRArc) are selectively activated in T1D. Activation of LepRArc neurons, Arc GABAergic (GABAArc) neurons, or arcuate AgRP neurons, is able to reverse the leptin’s rescuing effect. Conversely, inhibition of GABAArc neurons, but not AgRP neurons, produces leptin-mimicking rescuing effects. Further, AgRP neuron function is not required for T1D hyperglycemia or leptin’s rescuing effects. Finally, T1D LepRArc neurons show defective nutrient sensing and signs of cellular energy deprivation, which are …

Acetyl-Coa And Metabolite Fluxes Regulate White Adipose Tissue Expansion, Jessica B Felix, Aaron R Cox, Sean M Hartig

Faculty, Staff and Students Publications

White adipose tissue (WAT) depends on coordinated regulation of transcriptional and metabolic pathways to respond to whole-body energy demands. We highlight metabolites that contribute to biosynthetic reactions for WAT expansion. Recent studies have precisely defined how byproducts of carbohydrate and lipid metabolism affect physiological and endocrine functions in adipocytes. We emphasize the critical emerging roles of short-chain fatty acids (SCFAs) and tricarboxylic acid (TCA) cycle metabolites that connect lipogenesis to WAT energy balance and endocrine functions. These insights address how adipocytes use small molecules generated from central carbon metabolism to measure responses to nutritional stress.

Mitophagy Deficiency Increases Nlrp3 To Induce Brown Fat Dysfunction In Mice, Myoung Seok Ko, Ji Young Yun, In-Jeoung Baek, Jung Eun Jang, Jung Jin Hwang, Seung Eun Lee, Seung-Ho Heo, David A Bader, Chul-Ho Lee, Jaeseok Han, Jong-Seok Moon, Jae Man Lee, Eun-Gyoung Hong, In-Kyu Lee, Seong Who Kim, Joong Yeol Park, Sean M Hartig, Un Jung Kang, David D Moore, Eun Hee Koh, Ki-Up Lee

Faculty, Staff and Students Publications

Although macroautophagy/autophagy deficiency causes degenerative diseases, the deletion of essential autophagy genes in adipocytes paradoxically reduces body weight. Brown adipose tissue (BAT) plays an important role in body weight regulation and metabolic control. However, the key cellular mechanisms that maintain BAT function remain poorly understood. in this study, we showed that global or brown adipocyte-specific deletion of pink1, a Parkinson disease-related gene involved in selective mitochondrial autophagy (mitophagy), induced BAT dysfunction, and obesity-prone type in mice. Defective mitochondrial function is among the upstream signals that activate the NLRP3 inflammasome. NLRP3 was induced in brown adipocyte precursors (BAPs) from pink1 …

Rev-Erb In Gabaergic Neurons Controls Diurnal Hepatic Insulin Sensitivity, Guolian Ding, Xin Li, Xinguo Hou, Wenjun Zhou, Yingyun Gong, Fuqiang Liu, Yanlin He, Jia Song, Jing Wang, Paul Basil, Wenbo Li, Sichong Qian, Pradip Saha, Jinbang Wang, Chen Cui, Tingting Yang, Kexin Zou, Younghun Han, Christopher I Amos, Yong Xu, Li Chen, Zheng Sun

Faculty, Staff and Students Publications

Systemic insulin sensitivity shows diurnal rhythm with a peak at wakening1,2. The molecular mechanism underlying such a temporal pattern is unclear. Here we demonstrate that nuclear receptors Rev-erbα/β in the GABAergic neurons in the suprachiasmatic nucleus (SCNGABA) control the diurnal rhythm of insulin-mediated suppression of hepatic glucose production in mice, without affecting diurnal eating or locomotor behaviors under the regular light-dark cycles. Rev-erb regulates the rhythmic expression of genes involved in neurotransmission in the SCN and modulates the oscillatory firing activity of SCNGABA neurons. Chemogenetic stimulation of SCNGABA neurons at wakening causes glucose intolerance, while restoration …

An Inactivated Bacterium (Paraprobiotic) Expressing Bacillus Thuringiensis Cry5b As A Therapeutic For Ascaris And Parascaris Spp. Infections In Large Animals, Joseph F. Urban, Martin K. Nielsen, David Gazzola, Yue Xie, Ethiopia Beshah, Yan Hu, Hanchen Li, Florentina Rus, Kelly Flanagan, Austin Draper, Sridhar Vakalapudi, Robert W. Li, Gary R. Ostroff, Raffi V. Aroian

Maxwell H. Gluck Equine Research Center Faculty Publications

Ascaris and Parascaris are important parasites in the family Ascarididae, large, ubiquitous intestinal-dwelling nematodes infecting all classes of vertebrates. Parasitic nematode drug resistance in veterinary medicine and drug recalcitrance in human medicine are increasing worldwide, with few if any new therapeutic classes on the horizon. Some of these parasites are zoonotic, e.g., Ascaris is passed from humans to pigs and vice versa. The development of new therapies against this family of parasites would have major implications for both human and livestock health. Here we tested the therapeutic ability of a paraprobiotic or dead probiotic that expresses the Bacillus …

Serial Block-Face Scanning Electron Microscopy (Sbf-Sem) Of Biological Tissue Samples, Justin A Courson, Paul T Landry, Thao Do, Eric Spehlmann, Pascal J Lafontant, Nimesh Patel, Rolando E Rumbaut, Alan R Burns

Faculty, Staff and Students Publications

Serial block-face scanning electron microscopy (SBF-SEM) allows for the collection of hundreds to thousands of serially-registered ultrastructural images, offering an unprecedented three-dimensional view of tissue microanatomy. While SBF-SEM has seen an exponential increase in use in recent years, technical aspects such as proper tissue preparation and imaging parameters are paramount for the success of this imaging modality. This imaging system benefits from the automated nature of the device, allowing one to leave the microscope unattended during the imaging process, with the automated collection of hundreds of images possible in a single day. However, without appropriate tissue preparation cellular ultrastructure can …

Loss Of Bone Morphogenetic Protein-Binding Endothelial Regulator Causes Insulin Resistance, Hua Mao, Luge Li, Qiying Fan, Aude Angelini, Pradip K Saha, Huaizhu Wu, Christie M Ballantyne, Sean M Hartig, Liang Xie, Xinchun Pi

Faculty, Staff and Students Publications

Accumulating evidence suggests that chronic inflammation of metabolic tissues plays a causal role in obesity-induced insulin resistance. Yet, how specific endothelial factors impact metabolic tissues remains undefined. Bone morphogenetic protein (BMP)–binding endothelial regulator (BMPER) adapts endothelial cells to inflammatory stress in diverse organ microenvironments. Here, we demonstrate that BMPER is a driver of insulin sensitivity. Both global and endothelial cell-specific inducible knockout of BMPER cause hyperinsulinemia, glucose intolerance and insulin resistance without increasing inflammation in metabolic tissues in mice. BMPER can directly activate insulin signaling, which requires its internalization and interaction with Niemann-Pick C1 (NPC1), an integral membrane protein that …

Glucagon Blockade Restores Functional Β-Cell Mass In Type 1 Diabetic Mice And Enhances Function Of Human Islets, May-Yun Wang, E Danielle Dean, Ezekiel Quittner-Strom, Yi Zhu, Kamrul H Chowdhury, Zhuzhen Zhang, Shangang Zhao, Na Li, Reshing Ye, Young Lee, Yiyi Zhang, Shiuhwei Chen, Xinxin Yu, Derek C Leonard, Greg Poffenberger, Alison Von Deylen, S Kay Mccorkle, Amnon Schlegel, Kyle W Sloop, Alexander M Efanov, Ruth E Gimeno, Philipp E Scherer, Alvin C Powers, Roger H Unger, William L Holland

Faculty, Staff and Students Publications

We evaluated the potential for a monoclonal antibody antagonist of the glucagon receptor (Ab-4) to maintain glucose homeostasis in type 1 diabetic rodents. We noted durable and sustained improvements in glycemia which persist long after treatment withdrawal. Ab-4 promoted β-cell survival and enhanced the recovery of insulin+ islet mass with concomitant increases in circulating insulin and C peptide. In PANIC-ATTAC mice, an inducible model of β-cell apoptosis which allows for robust assessment of β-cell regeneration following caspase-8–induced diabetes, Ab-4 drove a 6.7-fold increase in β-cell mass. Lineage tracing suggests that this restoration of functional insulin-producing cells was at least partially …

The Crosstalk Between Cardiomyocyte Calcium And Inflammasome Signaling Pathways In Atrial Fibrillation, Xiaolei Wang, Xiaohui Chen, Dobromir Dobrev, Na Li

Faculty, Staff and Students Publications

Atrial fibrillation (AF) is the most frequent arrhythmia in adults. The prevalence and incidence of AF is going to increase substantially over the next a few decades. Because AF increases the risk of stroke, heart failure, dementia, and others, it severely impacts the quality of life, morbidity and mortality. Although the pathogenesis of AF is multifaceted and complex, focal ectopic activity and reentry are considered as the fundamental proarrhythmic mechanisms underlying AF development. Over the past 2 decades, large amount of evidence points to the key role of intracellular Ca2+ dysregulation in both initiation and maintenance of AF. More recently, …

Deficiency Of Stat1 In Cd11c+ Cells Alters Adipose Tissue Inflammation And Improves Metabolic Dysfunctions In Mice Fed A High-Fat Diet, Antu Antony, Zeqin Lian, Xiaoyuan Dai Perrard, Jerry Perrard, Hua Liu, Aaron R Cox, Pradip Saha, Lothar Hennighausen, Sean M Hartig, Christie M Ballantyne, Huaizhu Wu

Faculty, Staff and Students Publications

CD11c+ macrophages/dendritic cells (MDCs) are increased and display the classically activated M1-like phenotype in obese adipose tissue (AT) and may contribute to AT inflammation and insulin resistance. Stat1 is a key transcription factor for MDC polarization into the M1-like phenotype. Here, we examined the role of Stat1 in obesity-induced AT MDC polarization and inflammation and insulin resistance using mice with specific knockout of Stat1 in MDCs (cKO). Stat1 was upregulated and phosphorylated, indicating activation, early and persistently in AT and AT MDCs of wild-type mice fed a high-fat diet (HFD). Compared with littermate controls, cKO mice fed an HFD (16 …